Mobile Plaforms: A6X and Virtual Memory

Advanced Mac OS X Programming: The Big Nerd Ranch 7. Memory
1

Hi Mark,

On page 155 you state:

[quote]As programs request more and more memory from the system, the least recently used pages are written to disk, called “paging” or “swapping”, and the chunk of physical
memory is reused. iOS does not have this disk-based swapfile, so you will hit out of memory conditions sooner on that platform with desktop MacOSX.[/quote]

Do you know if this has been verified with the introduction of the A6X? The mobile hardware platforms are really getting to be super powerful (relative to earlier versions). I can’t understand why this wouldn’t be enabled for the ipad with retina display.

Thanks,
TB

2

Yep, no swap on iOS. The reasons I’ve heard relate to “disk” space, life-span of the flash memory (only so many writes can happen before it starts failing, and much work happens to even out the wear), as well as power. If you’re swapping on your phone, your battery probably won’t last much longer :slight_smile: